Improvement in connecting pins for bars of bridges



P. MUNZINGER.

CONNECTING PINS FOR. BARS 0F BRIDGES. No.184,888. Patented Nov.Z8, 1876.

rr STATES PATENT rrron.

PETER MUNZINGER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO MORRIS,TASKER & (10., (LIMITED,) OF'SAME PLACE.

IMPROVEMENT l N CONNECTING-PINS FOR BARS OF BRIDGES.

Specification forming part of Letters Patent No. 184,888, dated November28, 1876; application filed October 10,1876.

To all whom it may concern:

Be it known that I, PETER MUNZINGER, of the city and county ofPhiladelphia, in the State of Pennsylvania, have invented a new anduseful Improvement in Connecting-Pins for Eye-Bars, of which I herebydeclare the following to be a full, clear, and precise description, andsufficient to enable those skilled in the art to which my improvementappertains to comprehend and construct it, reference being had to theaccompanying drawing, forming a part of this specification.

My invention relates to bridge, scaffold, and truss building in general,and the like, and has for its object a reliable connecting-pin forstraining or eye bars; to which end it consists in the devicehereinafter described and claimed.

Of the drawings, in all of which similar letters of reference denotecorresponding parts, Figure 1 represents, in sectional plan, the oldform of connecting by a simple bolt, and shows, further, the excessiveiii-cutting of the threads upon the bolt-shank, to obviate the dangersresulting from which is the aim of this my improvement; Fig. 2, a topview of bars connected by my composite pin; and Fig. 3, a sectionthrough the same, disclosing the relative position and construction ofthe parts.

The disadvantages attending the cutting of the screw-thread too far upthe shank of the bolt a result almost impossible of avoidance,

by reason of the carelessness of workmen, and the difiiculty of gagingthe depth of the cut are that the straining-bar, which has its seat uponsuch over-cut portion, is either worn by the thread to the eventualloosing up and. twisting out of shape of the connection, or else shearsthe bolt itself off across the weakened in-cut portion.

To obviate these disadvantages I have invented a very simple device, tobe described by reference to the drawings, as follows: A

connection thus formed are reduced to a mini mum, for the hollowcylindrical pin is of the strongest form, to resist compressing-strains,while the side plates prevent a possibility of slipping and twisting offof the eye-bars, and the bolt, being used simply to confine, and itselfsufi'ering no strain, is suhjectedto no possibility of fracture ordamage whatever.

Having thus described my invention, I claim and desire to. secure byLetters Patent of the United States- The combination of the hollowcylindrical pin A, the side plates B, provided with circular bosses 0,adapted to fit direct within the core of the pin, and thus retainthemselves laterally in position, and a single central confining-bolt,D, adapted to pass completely through both side plates and pin, and tosecure the entire device together, so as to form an improved compositepin for the union of straining-bars, substantially as described.

In testimony whereof I have hereunto signed my name in the presence oftwo subscribing witnesses.

PETER MUNZINGER. Witnesses:

J. BONSALL TAYLOR, JOHN JOLLEY.

